This application is related to U.S. patent application Ser. No. 09/216,606, entitled xe2x80x9cMultilayered Ceramic Substrate Serving as Ink Manifold and Electrical Interconnection Platform for Multiple Printhead Diesxe2x80x9d filed on Dec. 17, 1998, assigned to the assignee of the present invention, and incorporated herein by reference. This application is related to U.S. patent application Ser. No. 09/648,564, entitled xe2x80x9cWide-Array Inkjet Printhead Assembly with Hybrid Carrier for Printhead Diesxe2x80x9d filed on Aug. 25, 2000, assigned to the assignee of the present invention, and incorporated herein by reference.
The present invention relates generally to inkjet printheads, and more particularly to a wide-array inkjet printhead assembly.
A conventional inkjet printing system includes a printhead, an ink supply which supplies liquid ink to the printhead, and an electronic controller which controls the printhead. The printhead ejects ink drops through a plurality of orifices or nozzles and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Typically, the orifices are arranged in one or more arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the printhead and the print medium are moved relative to each other.
In one arrangement, commonly referred to as a wide-array inkjet printing system, a plurality of individual printheads, also referred to as printhead dies, are mounted on a single carrier. As such, a number of nozzles and, therefore, an overall number of ink drops which can be ejected per second is increased. Since the overall number of drops which can be ejected per second is increased, printing speed can be increased with the wide-array inkjet printing system.
Mounting a plurality of printhead dies on a single carrier, however, requires that the single carrier perform several functions including fluid and electrical routing as well as printhead die support. More specifically, the single carrier must accommodate communication of ink between the ink supply and each of the printhead dies, accommodate communication of electrical signals between the electronic controller and each of the printhead dies, and provide a stable support for each of the printhead dies. Unfortunately, effectively combining these functions in one unitary structure is difficult.
Accordingly, a need exists for a carrier which provides support for a plurality of printhead dies while accommodating fluidic and electrical routing to each of the printhead dies.
One aspect of the present invention provides an inkjet printhead assembly. The inkjet printhead assembly includes a carrier including a substrate having a first side and a second side, and an electrical circuit disposed on a second side of the substrate. As such, a printhead die is mounted on a first side of the substrate and at least one electrical connector is electrically coupled to the electrical circuit and the printhead die.
In one embodiment, the electrical circuit includes a printed circuit board, wherein the printed circuit board and the substrate both have at least one ink passage extending therethrough. As such, the at least one ink passage communicates with the first side of the substrate and the printhead die for supplying ink thereto.
In one embodiment, the electrical circuit includes a first interface to which the at least one electrical connector is electrically coupled. In one embodiment, the first interface includes at least one electrical contact and the printhead die includes at least one electrical contact. Thus, the at least one electrical connector is electrically coupled to both the electrical contact of the first interface and the electrical contact of the printhead die.
In one embodiment, the substrate has at least one opening defined therein. As such, the electrical contact of the first interface is accessible through the opening and the electrical connector passes through the opening.
In one embodiment, the electrical connector includes a wire lead having a first end electrically coupled to the electrical contact of the first interface and a second end electrically coupled to the electrical contact of the printhead die.
In one embodiment, the electrical connector further includes a lead frame having a first tab electrically coupled to the electrical contact of the first interface and a second tab electrically coupled to the first end of the wire lead.
In one embodiment, the electrical connector further includes a lead pin having a first end electrically coupled to the electrical contact of the first interface and a second end electrically coupled to the first end of the wire lead.
In one embodiment, the electrical circuit includes a second interface. Thus, at least one electrical interconnect is electrically coupled to the second interface. In one embodiment, the electrical connector communicates with the first side of the substrate and the second side of the substrate. In one embodiment, the second side of the substrate is opposed to the first side of the substrate.
Another aspect of the present invention provides a method of forming an inkjet printhead assembly. The method includes providing a substrate having a first side and a second side, disposing an electrical circuit on the second side of the substrate, mounting a printhead die on the first side of the substrate, and electrically coupling at least one electrical connector with the electrical circuit and the printhead die.
Another aspect of the present invention provides a carrier adapted to receive a printhead die. The carrier includes a substrate having a first side adapted to receive the printhead die, an electrical circuit disposed on a second side of the substrate, and at least one electrical connector electrically coupled to the electrical circuit, wherein the at least one electrical connector communicates with the first side of the substrate.
Another aspect of the present invention provides a method of forming a carrier for a printhead die. The method includes providing a substrate having a first side adapted to receive the printhead die, disposing an electrical circuit on a second side of the substrate, and electrically coupling at least one electrical connector with the electrical circuit and communicating the at least one electrical connector with the first side of the substrate.
The present invention provides a carrier which provides support for a printhead die while accommodating fluidic and electrical routing to the printhead die.